2.4.3 Electric Fields

What are Electric Fields?

Direction of Electric Field Lines:

• Electric field lines show the direction a positive test charge would move: they point away from positive charges and towards negative charges.
• These field lines are always perpendicular (at right angles) to the surface of a charged object.

Strength of Electric Fields:

The strength of an electric field depends on two factors:

• Distance from the Charge: The closer you are to the charged object, the stronger the electric field. As you move further away, the field strength decreases.
• Amount of Charge: A larger charge produces a stronger electric field, indicated by more field lines.

Forces in Electric Fields:

• When a charged object is placed within another object's electric field, it experiences a force. This force can be either attractive (opposite charges) or repulsive (like charges).
• The strength of this force varies with distance: the closer the objects are, the stronger the force; the further apart they are, the weaker the force.
• Types of Electric Fields:
  • Uniform Electric Fields: These occur between two parallel plates with opposite charges, where the field lines are parallel and evenly spaced, indicating a constant field strength.
  • Radial Electric Fields: Found around a single point charge, where the field lines radiate outwards (for positive charges) or inwards (for negative charges) from the charge.

Diagrams